Systems and apparatus relating to seals for turbine engines

Abstract

A seal in a turbine of a combustion turbine engine is described. The seal is formed within a trench cavity defined between a rotor blade and a stator blade. The stator blade includes a sidewall projection and the rotor blade includes an angel wing projection extending toward the stator blade. The side wall projection overhangs the angel wing projection. The seal include: a port disposed on an inboard surface of the stator projection; and deflecting structure disposed on the angel wing projection. The deflecting structure may be configured to receive the fluid expelled from the port and deflect the fluid toward an inlet of the trench cavity.

We claim: 
     
       1. A seal in a turbine of a combustion turbine engine, wherein the seal is formed within a trench cavity defined between a rotor blade and a stator blade, wherein the stator blade includes a sidewall projection extending toward the rotor blade and the rotor blade includes an angel wing projection extending toward the stator blade, the side wall projection overhanging the angel wing projection, the seal comprising:
 a port disposed on an inboard surface of a stator projection; and 
 deflecting structure disposed on an outboard surface of the angel wing projection; 
 wherein:
 the port is configured to direct a fluid expelled therefrom toward the deflecting structure; 
 the deflecting structure is configured to receive the fluid expelled from the port and deflect the fluid toward an inlet of the trench cavity; 
 the side wall projection axially overlaps the angel wing projection; 
 the angel wing projection comprises a position inboard of the side wall projection; 
 the fluid comprises a coolant; 
 an inboard aimed reference line comprises a reference line originating at the port and aimed precisely in the inboard direction; 
 the port comprises an axial aimed direction within +/−20° of the inboard aimed reference line; and 
 the port comprises an circumferential aimed direction within +/−60° of the inboard aimed reference line. 
 
 
     
     
       2. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection comprises an axially extending rigid tooth;
 wherein the deflecting structure comprises a hooking curved portion positioned toward a distal end of the angel wing projection; 
 wherein the hooking curved portion comprises a concave curve that extends both axially and radially; 
 wherein a radial component of the hooking curved portion comprises an outboard direction; and 
 wherein an axial component of the hooking curved portion comprises an axial direction that is away from the rotor blade. 
 
     
     
       3. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection comprises an axially extending rigid tooth;
 wherein the deflecting structure comprises a canted linear portion positioned at a distal end of the angel wing projection; 
 wherein the canted linear portion comprises a linear portion that extends both axially and radially; 
 wherein a radial component of the canted linear portion comprises an outboard direction; and 
 wherein an axial component of the canted linear portion comprises an axial direction that is away from the rotor blade. 
 
     
     
       4. The combustion turbine engine seal according to  claim 1 , wherein, in respect to the inboard aimed reference line, a positive angle for the axial aimed direction of the port comprises one aimed away from the stator blade on which the port is disposed and a negative angle for the axial aimed direction of the port comprises one aimed toward the stator blade on which the port is disposed;
 wherein the axial aimed direction of the port comprises a positive angle; and 
 wherein the circumferential aimed direction is with a direction of rotation of the rotor blade. 
 
     
     
       5. The combustion turbine engine seal according to  claim 4 , wherein the axial aimed direction of the port comprises a positive angle direction between 5° and 20°. 
     
     
       6. The combustion turbine engine seal according to  claim 1 ,
 wherein the axial aimed direction of the port is within +/−10° of the inboard aimed reference line; 
 wherein the circumferential aimed direction of the port is within +/−30° of the inboard aimed reference line. 
 
     
     
       7. The combustion turbine engine seal according to  claim 1 , wherein the axial aimed direction of the port is substantially the same as the inboard aimed reference line; and
 wherein the circumferential aimed direction of the port is substantially the same as the inboard aimed reference line. 
 
     
     
       8. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection is disposed on an upstream side of the rotor blade and the port is disposed on the downstream side of the stator blade. 
     
     
       9. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection is disposed on a downstream side of the rotor blade and the port is disposed on the upstream side of the stator blade. 
     
     
       10. The combustion turbine engine seal according to  claim 1 , wherein the trench cavity comprises an axial gap that extends circumferentially between the rotating parts and the stationary parts of the turbine;
 wherein the trench cavity is formed between the trailing edge of the rotor blade and the leading edge of the stator blade, and the trailing edge of the stator blade and the leading edge of the rotor blade; 
 wherein the inlet of the trench cavity comprises a point at which the trench cavity intersects a main flow path through the turbine; 
 wherein the rotor blade includes an airfoil that resides in a main flow path through the turbine and interacts with a working fluid flowing therethrough, a dovetail for attaching the rotor blade to a rotor wheel, and, between the airfoil and the dovetail, a shank; 
 wherein the turbine stator blade includes an airfoil that resides in the main flow path through the turbine and interacts with the working fluid flowing therethrough and, radially inward of the airfoil, an inner sidewall that forms an inner boundary of the main flow path and, radially inward of the inner sidewall, a diaphragm that forms a second seal with one or more rotating components. 
 
     
     
       11. The combustion turbine engine seal according to  claim 1 , wherein:
 the turbine engine comprises at least a plurality of operating conditions; and 
 an axial width of the trench cavity varies depending upon the operating condition under which the turbine engine operates such that the trench cavity comprises a narrow width during a first operating condition and a wide width during a second operating condition; 
 wherein the port and the deflecting structure of the angel wing projection are configured such that, when the trench cavity comprises the narrow width, the port is well inside the deflecting structure of the angel wing projection; and 
 wherein the port and the deflecting structure of the angel wing projection are configured such that, when the trench cavity comprises the wide width, the port is just inside the deflecting structure of the angel wing projection. 
 
     
     
       12. The combustion turbine engine seal according to  claim 11 , wherein the turbine engine comprises an expected steady state operating condition; and
 wherein the port and the deflecting structure are configured such that during the expected steady state operating condition, the port and the deflecting structure comprise a preferred axial alignment. 
 
     
     
       13. The combustion turbine engine seal according to  claim 12 , wherein the preferred axial alignment comprises an alignment in which an axial position of the port falls within an axial range of the deflecting structure. 
     
     
       14. The combustion turbine engine seal according to  claim 12 , wherein the preferred axial alignment comprises one in which the port is aimed at the deflecting structure; and
 wherein an axial aimed direction of the port comprises one canted in opposition of a flow direction of ingested working fluid traveling from the inlet of the trench cavity to a wheelspace cavity. 
 
     
     
       15. The combustion turbine engine seal according to  claim 12 , wherein the port is configured to fluidly communicate with an interior cooling channel formed within the stator blade, the interior cooling channel being configured to circulate the coolant through the stator blade during operation of the combustion turbine engine; and
 wherein the port and the deflecting structure are configured such that, in operation, the deflected fluid forms an air curtain within the trench cavity that resists the ingestion of a working fluid through the trench cavity. 
 
     
     
       16. The combustion turbine engine seal according to  claim 12 , wherein a far edge of the deflecting structure comprises a position that aligns axially with a near edge of the port such that, in operation, substantially all of the fluid exiting the port is aimed inside of the deflecting structure. 
     
     
       17. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection extends along a circumferential width of the shank, and the port comprises a plurality of discrete ports spaced along a circumferential width of the sidewall. 
     
     
       18. The combustion turbine engine seal according to  claim 1 , wherein the angel wing projection extends along a circumferential width of the shank, and the port comprises a slot extending along a circumferential width of the sidewall.